Typical isolation models are studied and a New Application Security Isolation model called NASI is proposed, which is based on trusted computing technology and least privilege principle. This paper introduces the desi...Typical isolation models are studied and a New Application Security Isolation model called NASI is proposed, which is based on trusted computing technology and least privilege principle. This paper introduces the design ideas of NASI, gives out formal description and safety analysis for the model, and finally describes the implementation of prototype system based on NASI.展开更多
Phase transition in two dimensional molybdenum disulfide (MoS_2) can be induced by several methods and has been investigated for decades. Alkali metal insertion of MoS_2 had been proved an effective method to cause ph...Phase transition in two dimensional molybdenum disulfide (MoS_2) can be induced by several methods and has been investigated for decades. Alkali metal insertion of MoS_2 had been proved an effective method to cause phase transition early in 1970s, and has been gaining renewed interest recently, due to the possible application of MoS_2 in energy storage. The alkali metal intercalation of MoS_2 has been studied by various techniques, among which in-situ transmission electron microscopy (TEM) provides unique capability of real time resolving the structural evolution of the materials at high spatial resolutions. Here by in-situ TEM technique we investigated the structural evolution of MoS_2 upon lithium and sodium intercalation, along with transformation of the nanosheet and variation of the electron diffraction patterns. The intercalation process is accompanied by emergence of superstructures, which exist in several forms. The ion intercalation results in phase transition of MoS_2 from 2H to 1T, and the driving mechanism of the phase transition are discussed. The work provides a more comprehensive understanding of ion intercalation induced phase transition of MoS_2.展开更多
A chaotic algorithm for providing a solution to the bi-level Discrete Equilibrium Network Design Problem (NDP) is discussed following an introduction of the Discrete Network Design Problem (DNDP) model and Chaos O...A chaotic algorithm for providing a solution to the bi-level Discrete Equilibrium Network Design Problem (NDP) is discussed following an introduction of the Discrete Network Design Problem (DNDP) model and Chaos Optimization Algorithms (COA). A description of the chaotic approach for the DNDP model is described in details. Then a numerical example for the DNDP is carried out to investigate the chaotic approach. The results have been encouraging, indicating that the chaotic approach has great potential ability in finding the optimal solution of DNDP models.展开更多
文摘Typical isolation models are studied and a New Application Security Isolation model called NASI is proposed, which is based on trusted computing technology and least privilege principle. This paper introduces the design ideas of NASI, gives out formal description and safety analysis for the model, and finally describes the implementation of prototype system based on NASI.
基金supported by the Program from Chinese Academy of Sciences (ZDYZ2015-1, XDB07030100)the National Natural Science Foundation of China (11474337, 51421002, 51172273,221322304, 11290161)
文摘Phase transition in two dimensional molybdenum disulfide (MoS_2) can be induced by several methods and has been investigated for decades. Alkali metal insertion of MoS_2 had been proved an effective method to cause phase transition early in 1970s, and has been gaining renewed interest recently, due to the possible application of MoS_2 in energy storage. The alkali metal intercalation of MoS_2 has been studied by various techniques, among which in-situ transmission electron microscopy (TEM) provides unique capability of real time resolving the structural evolution of the materials at high spatial resolutions. Here by in-situ TEM technique we investigated the structural evolution of MoS_2 upon lithium and sodium intercalation, along with transformation of the nanosheet and variation of the electron diffraction patterns. The intercalation process is accompanied by emergence of superstructures, which exist in several forms. The ion intercalation results in phase transition of MoS_2 from 2H to 1T, and the driving mechanism of the phase transition are discussed. The work provides a more comprehensive understanding of ion intercalation induced phase transition of MoS_2.
基金This project is supported partly by National 0utstanding Young Investigation of National Natural Science Foundation of China(70225005,70471088,70501004 and 70501005), the Special Research Found for Doctoral Programs in State Education Ministry (20050004005), the 211 Project of Discipline Construction of Beijing Jiaotong University and Rencai Foundation of Beijing Jiaotong University (2003RC010)
文摘A chaotic algorithm for providing a solution to the bi-level Discrete Equilibrium Network Design Problem (NDP) is discussed following an introduction of the Discrete Network Design Problem (DNDP) model and Chaos Optimization Algorithms (COA). A description of the chaotic approach for the DNDP model is described in details. Then a numerical example for the DNDP is carried out to investigate the chaotic approach. The results have been encouraging, indicating that the chaotic approach has great potential ability in finding the optimal solution of DNDP models.